6.1-stable review patch. If anyone has any objections, please let me know.
------------------
From: Filipe Manana <fdmanana@xxxxxxxx>
[ Upstream commit fe4cd7ed128fe82ab9fe4f9fc8a73d4467699787 ]
At btrfs_load_zone_info() we have an error path that is dereferencing
the name of a device which is a RCU string but we are not holding a RCU
read lock, which is incorrect.
Fix this by using btrfs_err_in_rcu() instead of btrfs_err().
The problem is there since commit 08e11a3db098 ("btrfs: zoned: load zone's
allocation offset"), back then at btrfs_load_block_group_zone_info() but
then later on that code was factored out into the helper
btrfs_load_zone_info() by commit 09a46725cc84 ("btrfs: zoned: factor out
per-zone logic from btrfs_load_block_group_zone_info").
Fixes: 08e11a3db098 ("btrfs: zoned: load zone's allocation offset")
Reviewed-by: Johannes Thumshirn <johannes.thumshirn@xxxxxxx>
Reviewed-by: Qu Wenruo <wqu@xxxxxxxx>
Reviewed-by: Naohiro Aota <naohiro.aota@xxxxxxx>
Signed-off-by: Filipe Manana <fdmanana@xxxxxxxx>
Reviewed-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: David Sterba <dsterba@xxxxxxxx>
Signed-off-by: Sasha Levin <sashal@xxxxxxxxxx>
---
fs/btrfs/zoned.c | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)
diff --git a/fs/btrfs/zoned.c b/fs/btrfs/zoned.c
index 2c42e85a3e269..794526ab90d26 100644
--- a/fs/btrfs/zoned.c
+++ b/fs/btrfs/zoned.c
@@ -1345,7 +1345,7 @@ static int btrfs_load_zone_info(struct btrfs_fs_info *fs_info, int zone_idx,
switch (zone.cond) {
case BLK_ZONE_COND_OFFLINE:
case BLK_ZONE_COND_READONLY:
- btrfs_err(fs_info,
+ btrfs_err_in_rcu(fs_info,
"zoned: offline/readonly zone %llu on device %s (devid %llu)",
(info->physical >> device->zone_info->zone_size_shift),
rcu_str_deref(device->name), device->devid);
--
2.43.0
